foo.cc: In function 'int main()':
foo.cc:16:39: warning: statement has no effect [-Wunused-value]
   16 |                                 a[i+1]==0;
      |                                 ~~~~~~^~~
foo.cc:12:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   12 |                 if(a[i]!=a[i+1])
      |                   ^

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